Please Help!! Sds Users Read This!

[Garrett76Zt]

so im trying to leave chicago and drive to FL, my wife and i are just waiting for me to figure out whats wrong with the car.

 

I will try and be very concise in describing the problem(s):

 

(BACKGROUND INFO)

1. When the car first got running the car would only run on the battery, alt not charging. Alternator is good though. Battery is brand new. Turns out its that charge bulb in the dash that isnt telling the alternator to turn on. So i wired the plug in the alternator straight to the battery. This brought the alternator online no problem. just today i wired in a relay just to be safe and voltage actually rose some. Voltage is somewhat steady but kinda high like low 14's at idle and high 14's at higher rpms. Just went for a drive and everything was fine for about 10 min then i lost all the stock gauges and my Autometer tach. All went dead.

 

( Main Problem(s) )

 

1. Car dies at idle - this has been happening for a few days. Every so often when i pull up to a light and the car is idling perfectly it will just die. Seems like ignition is cutting out, cause when i crank it back up it backfires on the extra fuel in the cylinders. but it does crank back up and then idle until sporatically dying again.

 

2. Car misfires badly and dies above 2k rpm - This just started happening last night after my dyno session. I didnt mess with any timing maps or anything in the sds. The car will be running just fine, nice and smooth then all the sudden misfire really badly and die, sometimes bad enough that it blows the fuse to the coilpacks(another reason why i think its ignition related)

 

 

Things i've checked:

1. Fusible links all check out ok

2. 3 grounds running to SDS ECU

3. Switched power for SDS is solid connection

4. Tried running power to the coilpacks directly to the battery, thinking perhaps the ignition switch is being overloaded or something.

5. Checked my hall sensor mount and its still solid, maybe my magnets are falling out or something

 

 

Anyways i cleaned up some connections, replaced fuses and took another drive . . . it still died out twice while i was at red lights but the car ran awesome all the way through the powerband . . . for about 10 min. Then same thing, started misfiring(and backfiring) sometimes when above 2k rpm

 

I talked with SDS today and he had me hunt around a few things without any real luck. they are closed now.

 

Now is the time to mention anything and everything to figure this crap out, We really need to get on the road soon, but no way am i doing that with the car running like it is. HELP ME OUT GUYS!

[Garrett76Zt]

Anybody? Pullin my hair out here.

[cheftrd]

As far as the idle, I would say that's just a bad tune in those ranges if it does it consistently. Check MAP. It needs to stay stable and not fluctuate between more than three ranges. Any ranges the idle fluctuates between need to be the same fuel value. When it dies, is it after you have engine braked to a stop? If so, try killing the fuel in the decel map ranges. You may be rich under engine braking and loading up with unburned fuel; when you push in the clutch, it won't want to idle.

 

Where are the coils? With the hit and miss ignition thing, I suspect heat, either from the engine or the coils themselves. If you run too much timing in the lower rpm's it overworks the drivers. For instance, if your base timing is 10 deg. at idle and you pull 20 more under vacuum advance for 30 total, under cruising conditions at 2500 rpm you could end up with as much as 45-55 degrees. The driver hates this at lower rpm's. I've also had cdi's and bad plug wires give me hit and miss problems with a hot-engine misfire. Blowing the fuse under a hard misfire is normal; It's protection for the coil drivers.

 

If you are using the stock rubber insulated pulley, the outer ring will sometimes slip causing your timing to appear OK on the programmer and light, but be way off on the engine. This will cause the timing to be retarded and will also cause the exact same problems you are having at idle and high load misfire. Put the engine at TDC (not with the timing marks) and see if the pulley marks agree.

 

There's a 99% chance that there's nothing wrong with the SDS. I have installed A LOT of SDS systems, and never had a problem that was the systems fault, so exhaust all other potential problems first, before wasting time with the ECU.

[Garrett76Zt]

thanks for the reply,

 

As far as idle goes this happens when the car is sitting in the garage idling, not just while im driving. it will sit there and idle perfectly for several minutes and then all the sudden die, there is no stumble or anything first, goes from perfect to dead just like that.

 

I'm not sure i fully follow what you're saying about the timing/coilpacks. I definitely think it could be temperature related since the car runs for several minutes just fine until everything gets real hot. Keep in mind this is a problem that i was not having the past few days and all the sudden appeared last night. what exactly can i check to see if what you're saying is true?

 

Is there a possiblity that any of these problems could be related to either the water temp sensor or the air temp sensor? I say that cause i have the air temp sensor mounted on my sheet metal intake manifold and last night it got REALLY hot after multiple passes on the dyno. Tomorrow i am putting a fresh sensor in the IC piping just before the TB like the manual says to.

 

I also want to rule out that it has anything to do with my alternator issues. right now i'm trying to figure out why all my gauges went out. all the bulbs still light up but they all went dead at the same time.

[Guest nizmo]

I ran into the same prob last year, could not find main prob so I took the easy route: first I took out every piece of wire from the entire car then I dropped in a nice little sbf and rewired everything